Protective housing for coils



Aug. 24, I937. w. H. REICHARD PROTECTIVE HOUSING FOR COILS Filed Sept; 11, 1935 m m m m 2 m 8 8 M .V m 2 2 o 1 o 0 Q 9 o 0 Q N W n n- 8 2 a H 2 Q on H E 2 v 9 6w fl q a q g m mu w mm m. m wa u 9 Q 8 an em 2 w 2 R 9 mm T N S m g km .2 Q E on Patented. Aug. 24, 1 937 Wade n. Reinhard, Rochester, N.

Y., assitnor to General Railway Signal Company, Rochester,

N. it.

Application September 5 Claims.

This invention relates to electric coils, and more particularly to a protective housing for car-carried receiver coils of the type employed in railway train control systems and the like.

In railway train control systems, a receiver coil on a magnetic core structure is' carried by the locomotive in rather close proximity to the track rails in order to be inductively afiected by I current in the track rails. Such coils are ex-- posed to moisture, oil and other deteriorating substances and are continuously subjected to the jars and vibrations of the train, all of which tend to alter the coil characteristics by causing broken wires, short circuits, and the like. It has also been found that as these coils must be mounted directly above the rails, various loose objects along the trackway such as stones and the like are thrown against the coils with considerable force thereby puncturing or gradually wearing away the outer covering 0! the coils andcausing considerable damage to the windings thereof.

These coils are also occasionally exposed to rather high temperatures such as caused by steam emitted from the locomotive cylinders or the like which likewise may damage or deteriorate the coil insulation.

In view of the above and other considerations,

it is proposed in accordance with the present invention to provide a protective housing for coils which prevents damage to the coil wires or insulation by shocks or vibration, which is not easily damaged byabrasive action thereon and which is moisture, oil and heat repellent. More speciflcally, it is proposed to provide a coil housing 01' rubber in a pliable form which is treated to resist abrasion and deteriorating substances, and which rubber housing resiliently suspends the windings oi the coil around a magnetic core, whereby to prevent shocks and vibrations of the core from being transmitted to the coil. It is also proposed to provide such a coil housing which is conveniently removable from its supporting magnetic core.

Other objects, purposes and characteristic ieatures of the present invention will be apparent as the description thereof progresses, during which reference will be made to the accompanying drawing, in which:

Fig. 1 is an elevational view of a complete receiver coil arranged in accordance with the present invention and shown in its normal carcarried position above a railway track rail.

Fig. 2 is an enlarged elevational view of the coil shown in Fig. 1 with a part thereof shown in section.

11, 1935, Serial No. 40,112 (Cl. -461) Fig. 3 is an elevatlonal view of the coil shown in Fig. 2, the partial section in Fig. 2 being taken substantially on line 2-2 of Fig. 3.

In the usual type of railway train control systems, receiver coils on magnetic cores are carried in front of .the first pair of wheels of the locomotive directly above each track rail. In this manner, the alternating train control current flowing in the rails produces a flux which is collected by the magnetic core to pass through the receiver coils in a manner to induce current therein which conditions the car-carried train control apparatus in accordance with forward trailic conditions.

In Fig. 1 of the accompanying drawing, such a magnetic receiver structure is illustrated as including a laminated horizontal core 4 extending transversely above a track rail 5 illustrated in section. The extending ends of the core 5 are magnetically joined 'to laminated pole pieces clamped between upright supporting plates 5 by through bolts 1, the ends of the laminated core *2 being also clamped between the plates E by through bolts 8. Inasmuchas it is considered advisable to electrically insulate the core pieces from the supporting plates 6, an insulating plate 9 is provided between each of the plates t and the laminated core and pole pieces, and likewise, suitable means may be employed such as insulated sleeves to electrically insulate the body portions of the through bolts I and 8 from the core pieces. Hanger members iii are attached to the upper ends 01' plates 6 such as by welding, and the hanger members ID are adapted to mount the magnetic structure thus formed on the railway vehicle.

A receiver coil is provided on the central portion of the core 4 which is constructed in accordance with the present invention as more clearly shown in Fig. 2 and Fig. 3. Referring to Fig. 2, a ring-shaped coil i2 is wound on a suitable arbor or the like to the required number of turns and of suitable insulated wire and taped or otherwise retained in its cylindrical shape of the proper dimensions. Lead wires I: are suitably attached to the ends of the winding, and the coil may be impregnated with suitable insulating compound in the usual manner.

The coil I2 is entirely surrounded by a housing formed by oppositely arranged molded rubber cases I! and IS. The cases I! and it are molded from mechanical-grade rubber in a pliable state, as, for example, these cases I! and it may be molded of the same material and pliability as that employed in treads of high grade pneumatic tires. In other words, a pliable abrasion-resistive material is employed in the molded cases I and I6 which is impervious to moisture and is not rapidly deteriorated by oil or heat.

5 The cases I5 and I6 each have outer cylindrical surfaces and are substantially E-shaped in cross section as shown in Fig. 2, the centers being provided with aligning through openings receiving and closely fitting around the substantially square core 4. In this manner, substantially half of the coil I2 is receivedby a hollow cylindrical interior of each of the cases I5 and I6, the two cases I5 and I6 jointly forming an enclosure for the complete coil I2 as may be seen in the sectional view of case I6 in Fig. 2. The cases I5 and I6 are of course assembled from the respective ends of coil I2 so that their inner ends abut as shown, and these abutting ends are carefully sealed with a suitable rubber cement or the like.

The cases thus form a complete enclosure for the coil I2 wherein a rather thick sleeve of pliable rubber is formed separating the inner surface of the coil I2 from the core 4, and a similar outer sleeve is formed of substantially the same thickness surrounding the outer sur-' face of the coil I2. The closed ends of .the cases I5 and I6 are provided with integral webs I5 and I6 extending vertically throughout the di- 3o ameters of the cases, and as may be seen in Fig.

3, these webs I5 and I6 are wider than the core 4.

The inner portions of the cases I5 and I6 which surround a core 4 as well as the outer 35 portion surrounding the coil I2 are provided with aligning horizontal holes receiving through bolts I8, whereby the two cases I5 and I6 are assembled around the coil I2. In the illustrated form shown in Fig. 3, four through bolts I8 are provided through the inner portion of the cases I5 and I6 which bolts extend through the web I5 and I6 the heads of the lower two of these bolts being held by a strap I9 resting in a recess in the web I6 while nuts 20 on these four inner 45 bolts I8 engage similar straps resting in recesses in the web I5 In a similar manner, two upper and two lower bolts I8 through the outer portion of the cases I5 and I6 pass through the webs I5 and I6, the heads of these bolts and nuts 20 threaded thereon being held by respective arcuate straps 2I, while the outer side portions of the cases I5 and I6 are clamped by four shorter through bolts iii, the heads of these bolts and their nuts 20 being held by respective longer arcuate straps 22. In this arrangement, the through bolts I8 not only retain the two cases I5 and I6 in their assembled position but also serve to reinforce the sides of these rubber cases I5 and I6.

A metal bushing 24 is molded into the upper portion of the web I6 of the right hand case I6- to thereby form a passage communicating with the interior of the coil housing for bringing out the lead wires I3. The bushing 24 is provided with inner and outer flanges, the outer flange being flush with the surface of the web I6 and shaped as shown in Fig. 3 to receive the heads of the four upper through bolts I8. A metal conduit fitting 25 is clamped against the outer surface of the bushing 24 by stud bolts 26 passing through horizontally extending'ears on the fitting 25 and threaded into bushing 24.

The hole in bushing 24 is preferably tapered as shown in Fig. 2, and a convenient means for 75 closing this opening around the lead wires I3 is provided by a pliable rubber plug 21 having spaced holes receiving the lead wires I3. A rigid disc 28 of insulating material also having holes receiving the lead wires I3 is provided between the plug 21 and the fitting 25 whereby the pliable plug 21 is compressed when assembling the fitting 25 to thoroughly seal the opening around the lead wires I3. The use of the rubber plug 21 however is optional as the opening around the lead wires I3 may be sealed with suitable thermo-plastic insulating compound.

The completely enclosed coil is detachably retained on the core 4 by bolts 36, one passing through the center of each of the webs I5 and I6 of the rubber cases I5 and I6. and through holes in the core 4;. The rubber webs I5 and I6 are protected from the heads of bolts 30 and nuts 3i threaded thereon by enlarged washers 32.

An electric coil has thus been provided which is particularly adapted for use in train control systems wherein the coils are continually subjected to adverse conditions. The windings of the present coil are resiliently suspended around the magnetic core whereby the shocks and vibrations to which the core is continually subjected are not transmitted to the windings, but rather these shocks and vibrations are substantially absorbed by the resilient rubber sleeve separating the coil from the core.

The present coil is further protected by a complete housing of resilient material which not only protects the windings from external shock due to flying stones and the like but also offers a maximum of resistance to the abrasive action of objects engaging the coil housing. A coil constructed in accordance with the present inven-- tion has the further advantage of being entirely impervious to moisture and other substances which might deteriorate or alter the characteristics of the windings, and the coil housing is not rapidly deteriorated by oil, heat or any other various substances or conditions ordinarily encountered along a railway system. The present coil is also a separate unit detachable from its magnetic core to thereby permit such coils to be replaced on the same core structure and membled apart from the magnetic core.

The above rather specific description of one form of the present invention is given solely by way of example, and is not intended, in any manner whatsoever, in a limiting sense. It is to be understood that various modifications, adaptations and alterations may be applied to meet the requirements of practice without in any manner departing from the spirit or scope of the invention, except as limited by the appended claims.

What I claim is:

1. In a car-carried receiver coil, a magnetic core, windings around the core and spaced therefrom, oppositely arranged pliable molded rubber cases completely enclosing the windings and having each an integral sleeve portion separating the windings from the core and an outer portion covering the winding, whereby to resiliently suspend the windings around the core and protect the windings.

2. In a car-carried receiver coil, a magnetic core, windings around the core, oppositely arranged pliable molded rubber cases completely enclosing the windings, and means sealing the cases around the windings, said cases having integral abutting sleeve portions separating the windings from the core whereby to resiliently suspend the windings around the core.

3. In a housing for train control receiver coils,

two cylindrical molded cases of pliable mechanical-grade rubber having closed outer ends and open abutting inner ends, through bolts for assembling the two cases around the coil, and integral abutting center portions in the cases having aligning apertures for receiving a magnetic core.

4. In a housing for train control receiver coils, two cylindrical molded cases of pliable mechanical-grade rubber having outer closed ends and open abutting inner ends', means for assembling the two cases around the coil, integral abutting apertures for receiving a magnetic core, and integrai end portions on the cases for removable attachment to the magnetic core.

5. In a housing for train control receiver coils having magnetic cores, two molded cases of mechanical-grade rubber for completely enclosing the coil, integral sleeves in the cases separating the coil from the magnetic core, a metal bushing molded into one of the casings, and means 10 for attaching a conduit to the bushing. WADE H. REICHARD. 

